Segmented ring guide for rolling mill laying head

ABSTRACT

A laying has a quill rotatable about an axis, and a pipe carried on the quill. The pipe has an entry end arranged to receive a product, and an intermediate portion defining a curved guide path leading from the entry and to a delivery end spaced radially from the quill axis and from which the product is discharged as a helical series of rings. A guide defines a helical extension of the guide path, and comprises a helical support plate projecting outwardly from the quill. A plurality of channel-shaped guide sections supported end to end on the support plate. The guide sections form a segmented radially outwardly facing helical trough surrounded by a cylindrical shroud that cooperates with the guide sections to definee radially and axially confined helical extension of the guide path.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority of provisional patentapplication Serial No. 60/340,180 filed on Dec. 14, 2001.

BACKGROUND OF DISCUSSION

[0002] 1. Field of the Invention

[0003] This invention relates to high speed rod rolling mills, and isconcerned in particular with an improvement to the laying heads employedin such mills to form the hot rolled product into a series of rings.

[0004] 2. Description of the Prior Art

[0005] With reference to FIG. 1, a typical laying head includes ahousing 10 containing a rotatably driven hollow quill 12. A threedimensionally curved laying pipe 14 is carried by the quill 12. Thelaying pipe has an entry end 14 a aligned with the rotational axis X ofthe quill, and a curved intermediate section 14 b leading to a deliveryend 14 c spaced radially from axis X.

[0006] Hot rolled steel rod is delivered to the entry end 14 a of thedelivery pipe along axis X, and exits from the delivery end 14 c as ahelical formation of rings.

[0007] Upon exiting from the delivery end 14 c of the laying pipe, therings are additionally confined and moved forward by a helical trough 16surrounded by a cylindrical shroud 18.

[0008] The guide trough 16 is configured and dimensioned to coact withthe shroud 18 in providing an axially and radially confined helicalextension of the guide path defined by the laying pipe. Although thisextended confinement has proven to be highly beneficial in resistingdistortion and kinking of the tail ends of products passing through thelaying head, the unitary instruction of the guide trough has given riseto certain difficulties. For example, the materials that can be readilyformed or machined into a helical configuration are relatively soft andthus prone to accelerated wear caused by frictional contact with the hotrolled product. Although accelerated frictional wear typically occursonly locally along short sections of the guide path, the entire troughmust be replaced when the affected sections are no longer serviceable.Also, since the dimensions of the guide trough are selected to closelyconfine a particular product size, a change in the rolling schedule to adifferent product size will usually require replacing the entire guidetrough with another trough properly dimensioned to handle the newproduct.

SUMMARY OF THE INVENTION

[0009] In accordance with the present invention, the known unitary guidetrough is replaced by a plurality of channel-shaped guide sectionscarried on the periphery of a helical support plate. The guide sectionsare preferably identical, spaced one from the other, and removablysecured to the support plate. With this arrangement, the support platemay be fabricated from one material selected for it strength andformability, e.g., ASTM A502, and the guide sections may be cast ormachined from a different material selected for its resistance tofrictional wear, e.g., ASTM 4140. Guide sections that undergoaccelerated wear can be replaced while allowing the others to remain inplace for continued extended use. A change in product size can bereadily accommodated by simply changing only the guide sections withouthaving to also replace the helical support plate.

[0010] These and other features and advantages of the present inventionwill now be described in greater detail with reference to theaccompanying drawings, wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

[0011]FIG. 1 is a partially sectioned side view of a typical layinghead;

[0012]FIG. 2 is a perspective view of the laying head quill and layingpipe equipped with a helical outport plate and segmented guide trough inaccordance with a preferred embodiment of the present invention;

[0013]FIG. 3 is a perspective view of the segmented guide trough andhelical support plate;

[0014]FIG. 4 is an exploded perspective view of the components shown inFIG. 3;

[0015]FIG. 5 is a perspective view of the helical support plate; and,

[0016]FIG. 6 is an end view of one of the trough segments.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0017] It will be seen by additional reference to FIG. 2 that a helicaltrough 16′ in accordance with the present invention is made up ofchannel-shaped guide segments 20 supported end-to-end on a helicalsupport plate 22 having a hub 24 removably secured to the end of thequill 12.

[0018]FIG. 3 shows the assembly of the helical support plate 22 andguide segments 20 removed from the quill, FIG. 4 is an exploded view ofthe components of the assembly, FIG. 5 shows the helical support plate22 by itself, and FIG. 6 shows and end view of a typical guide segment.The individual guide segments 20 have generally U-shaped guide channelswith mounting flanges 26. The mounting flanges 26 are angularly offsetwith respect to their respective guide channels, and are advantageouslyprovided with laterally projecting shoulders 28 configured anddimensioned to be seated in locating grooves 30 in flat recessedmounting surfaces 31 located around the flank of the helical supportplate 22. The guide segments are removably attached centrally by bolts32 or the like, and are preferably spaced one from the other as shown inFIGS. 2 and 3 at 34 in order to accommodate thermal expansion.

[0019] The guide segments 20 may comprise dimensionally accurateinvestment castings, cast from light weight materials, e.g., titanium.The guide segments may also be provided with wear and heat resistantceramic liners.

[0020] When individual guide segments experience accelerated wear, theymay be replaced without replacing those that experience lesser wear.Also, when a different product size is being rolled, only the guidesegments need to be changed.

We claim:
 1. In a laying head for forming an axially moving elongatedproduct into a helical series of rings, said laying head having a quillrotatable about an axis, and a pipe carried on said quill, said pipehaving an entry end aligned with said axis and arranged to receive saidproduct, and having an intermediate portion defining a curved guide pathleading from said entry and to a delivery end spaced radially from saidaxis and from which said product is discharged as said helical series ofrings, a guide defining a helical extension of said guide path, saidguide comprising: a helical support plate projecting outwardly from saidquill; a plurality of channel-shaped guide sections supported end to endon said guide plate, said guide sections forming a segmented radiallyoutwardly facing helical trough; and a cylindrical shroud surroundingand cooperating with said guide sections to define a radially andaxially confined helical extension of said guide path.
 2. The guide ofclaim 1 wherein said guide sections are removably secured to saidhelical support plate.
 3. The guide of claim 1 wherein said guidesections are spaced one from the other along the periphery of saidsupport plate.
 4. The guide of claim 3 wherein said guide sections areprovided with flanges protruding radially inwardly along a flank of saidguide plates, and wherein said flanges are secured centrally to saidflank.
 5. The guide of claim 4 wherein said flank has flat mountingsurfaces against which said flanges are secured.
 6. The guide of claim 5wherein said flanges are provided with bosses projecting laterally intogrooves in said flat mounting surfaces.
 7. The guide of claim 1 whereinsaid guide segments are identical and interchangeable one for the other.8. The guide of claim 1 wherein said guide segments are formed from amaterial which has a greater resistance to frictional wear as comparedto the resistance to frictional wear of the material of said supportplate.
 9. The guide of claim 1 wherein said support plate is removablysecured to said quill.
 10. The guide of claim 4 wherein said flanges areangularly offset with respect to the respective guide sections.